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Friendly Ball is an activated item added in Afterbirth.
- Once thrown, the Friendly Ball will instantly capture any non-boss enemy it hits, removing them from the room.
- The next time the Friendly Ball is thrown, it will release the previously captured enemy as a friendly enemy.
- Released enemies persist between rooms and floors and will follow Isaac until they die.
- Unlike typical charmed enemies, the released enemy cannot harm Isaac, and he doesn't need to defeat them to clear a room.
- All enemies that aren't invincible and/or designated as a boss or mini boss are able to be captured by the friendly ball. This includes enemies summoned from bosses such as Brownie's spawned Dips or The Cage's unique Vises.
- Although usefulness may vary, enemies that preserve themselves or are capable of Brimstone are far more beneficial than others. For example, capturing a Host or a Walking Host is highly beneficial as a stationary Host is likely not to get hit by other enemies and a Walking Host will lower its head further when taking a lot of damage, making the walking variants effective against bosses since it deals contact damage while rarely revealing its weak spot.
- It is generally wasteful to use this item on Mulligans and their variants as they will immediately rush towards enemies and try to kill themselves, leaving behind friendly debris.
- Another great option is to capture a Globin or a superior Gazing Globin, as once a Globin dies from contact damage from an enemy, it will become stationary and regenerate until it rises again to kill more enemies. The Gazing Globin is especially useful as once it dies, it will actively back away from potential threats, monumentally increasing its longevity.
- Wall Creeps, Rage Creeps, and The Thing also prove useful because they stick to walls, backing far away from any potential danger they might encounter. It's not recommended to use a Blind Creep, as though they have a good longevity, they cannot aim.
- Round Worms and their lookalikes are work surprisingly well as an ally as they shoot foes from far away and rarely ever get hurt.
- Possibly the best enemies to capture are Mom's Hand and Mom's Dead Hand as they will both one-shot almost all normal enemies and greatly damage most bosses with an incredibly small window for the hands to be hit.
- Finally, the most offensively capable enemies are Vises, Double Vises, Bloodshot Eyes, Scarred Double Vises, Red Ghosts, and Soul Suckers, as Brimstone lasers from enemies cause an obscene amount of damage to both enemies and most bosses.
- If the captured enemy is one that spawns enemies, those enemies will be friendly as well.
- If a Moter is caught, released, and killed, the two Attack flies that spawn will be non-charmed.
- If a Swinger is caught, released, and killed, it will spawn a non-charmed Maw or Globin.
- If a Dinga is caught and released, it will spawn aggressive, non-charmed Dips.
- If a Black Globin's Body is caught and released, it will spawn aggressive, non-charmed Spiders.
- These bugs have been fixed; all enemies resulting from previously charmed enemies now remain loyal to the player.
- If the captured enemy normally chases the player and deals contact damage, it will try to chase enemies after being released. If they attack an enemy that deals contact damage, the allies will suffer from it too.
- Most allies will immediately die on contact with a boss.
- If the ally is immune to damage (such as a Walking Host while its head is lowered), it will not take contact damage.
- If the captured enemy is a Solid White Champion, it will be completely invincible, as it cannot be killed until the room counts as being cleared, at which point it can be killed by spikes or a Wall Hugger.
- If the captured enemy is a Dark Red Champion, the enemy can regenerate after dying, granting a much longer lifespan. This can be very useful if you capture a Dark Red Hive because after each death the hive will spawn Big Spiders or Trites to take out other enemies, or if you capture a Dark Red Mulliboom who can explode repeatedly to faithfully damage enemies.
- If an enemy that leaves behind a trail of red creep is caught, the creep created by the charmed mob will still damage Isaac when he walks over it.
- This problem has been fixed. All creep created by a captured enemy will only hurt grounded enemies and not the player.
- The ball will only capture one segment of a Grub, one Buttlicker, or one Swarm Fly. However, when releasing a Swarm Fly, a new swarm is generated for it.
- If a Heart is caught and then released, a Mask can use the friendly heart to live even if its original heart is destroyed. The room will not be cleared unless the Mask is killed.
- The mask will ignore the friendly heart yet can still damage it. Bait the mask to charge towards the heart to destroy both.
- If a Gurgle is caught, the explosive Ipecac shots it fires will not hurt Isaac. This also applies to Splasher, Roundy, Gut, Walking Gut, Fred, Spit, and Blue Conjoined Fatty.
- The head of Rag Man can be captured by the ball while detached. It will not become a Ragling after being released, and only chases enemies by rolling.
- Poke Go and Mystery Egg spawn similar friendly enemies. My Shadow and Shade spawn chargers with the same status effect. Book of the Dead, while also spawning bone orbitals from deceased enemies, can also spawn Bonies or Black Bonies with a very similar perma-charm effect.
- If you have Skatole or Bursting Sack, friendly Fly/Spider enemies will also not be able to shoot, be slowed down, or be reverted to a weaker form, hindering this item's effectiveness on those enemies.
- Glowing Hour Glass will duplicate friendly enemies upon use.
- As of Booster Pack #5, this bug has been fixed.
- The item is a reference to Poké Balls from the Pokémon franchise.
PC 3WOS NSB1 (Treasure room adjacent to spawn)
PC MF7L HXQV (Treasure room adjacent to spawn) (Hard mode only)
Switch 0JV6 C0XG (First Golden Treasure Room)